JP2547931B2 - Detachment prevention pipe joint and its joining method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint of a type in which an opening of one pipe is inserted into a receiving end of the other pipe to join the two pipes.
In particular, the present invention relates to a structure and a joining method of a separation prevention pipe joint having a lock ring in a receiving portion for preventing the insertion opening from coming out of the receiving opening.

[0002]

2. Description of the Related Art As an example of a pipe joint having a function of preventing separation, one shown in FIG. 21 is known. In the figure, 101 is one tube having a receiving port 102, 103 is the other tube having an inserting port 104 inserted into the receiving port, and 105 is an inserting port 1 of the pipe 103.
04 is an insertion port protrusion provided on the outer peripheral surface of the tip, 106 is a receiving groove formed on the inner peripheral surface of the receiving port 102, 107 is a lock ring fitted into the receiving groove, and 108 is Backup ring, 1
09 is a rubber ring, 110 is a push ring, and 111 is a bolt nut. Figure
22 is a cross-sectional view taken along the line AA of FIG. 21, in which the lock ring 107 is reduced in diameter before the insertion port 104 is inserted into the reception port 102.
It is shown in a state in which it has been inserted into No. 2 and the diameter has been expanded in the receiving groove 106.

[0003]

By the way, in the above-mentioned conventional pipe joint, the lock ring 107 is divided into one in the circumferential direction, and the diameter can be expanded / contracted, so that the lock ring 107 can be securely connected at the time of joining. It is indispensable to confirm whether or not it is mounted in the receiving groove 106, and specifically the following work is required for this confirmation, and the work of setting the lock ring 107 as a whole becomes complicated and the workability is poor. There was a problem. (1) Before inserting the insertion opening 104 into the receiving opening 102, it is necessary to measure the gap a at the divided end portion by using a hole path or the like with the lock ring 107 being previously stored in the receiving opening groove 106 as shown in FIG. There is. After the measurement, the lock ring 107 is reduced in diameter and removed. (2) Insert the insertion slot 104 previously stored on the outer peripheral surface of the insertion slot into the receiving opening 102, reduce the diameter of the lock ring 107 with a throttle device (not shown), and then pass through the narrow gap between the receiving opening and the insertion opening to a predetermined position. It is necessary to insert to the position. (3) The insertion port 104 and the receiving port 102 when set in the predetermined positions
It is necessary to measure the gap between the divided ends again using the narrow space between and. (4) The gaps measured twice are compared, and if they are out of the specified range, it is necessary to redo again. (5) The above is all work in the digging pit, which is not preferable in terms of safety.

Therefore, the present invention solves the above-mentioned conventional problems and eliminates the gap measurement at the split end portion of the lock ring for confirming the mounting state of the lock ring before and after the insertion of the insertion opening into the receiving opening. An object of the present invention is to provide a pipe joint for preventing separation that can be performed and a joining method thereof.

[0005]

In order to achieve the above object, the invention of claim 1 provides a pipe joint as described above,
When the diameter of the lock ring is expanded, the inner diameter is larger than the outer diameter of the insertion opening projection, and when the diameter is reduced, the inner diameter is smaller than the outer diameter of the insertion opening so as to embrace the outer peripheral surface of the insertion opening.
With a bottom surface inner diameter slightly larger than the outer diameter of the lock ring expanded on the inner peripheral surface of the receiving opening facing the insertion protruding portion, a receiving opening concave portion capable of temporarily placing the lock ring when the lock ring is attached is formed, An annular step portion for locking the lock ring is formed on the inner peripheral surface of the receptacle facing the lock ring to be mounted, and the annular step from the receiving recess portion to the annular surface portion of the receiving portion between the annular step portion and the receiving recess portion. A tapered portion that gradually reduces in diameter toward the inner peripheral surface of the annular step portion and the outer peripheral surface of the annular step portion is engaged with each other when the lock ring is engaged with the annular step portion when the lock ring is mounted. A locking means for stopping is provided.

According to a second aspect of the present invention, there is provided a method for joining the separation preventing pipe joint according to the first aspect, wherein the lock ring is temporarily placed in the receiving recess with the diameter reduced, and the temporarily placed receiving recess is provided. The diameter of the lock ring is expanded with, and the expanded state is held by a holding member that is detachably attached to the lock ring so that the expanded state is released when pushed from the pipe axis direction by the insertion opening projection, and then the annular seal member is attached. Insert the insertion hole of the other tube deposited on the outer peripheral surface of the insertion hole into the receiving opening of one tube, push the holding member off with the projection of the insertion port, and then reduce the diameter by holding and releasing the holding member. A lock ring, which is held and fitted on the outer peripheral surface of the mouth, is positioned and locked on the annular step by the insertion mouth projection that engages by moving the insertion mouth from the receiving mouth in the pulling direction. After locking the ring and the annular step by the locking means, And wherein the pushing to a predetermined position toward the spigot into the socket on.

According to a third aspect of the present invention, in the joining method according to the second aspect, the lock ring is divided into one in the circumferential direction, and the holding member is provided between the surfaces of the split ends of the lock ring which face each other. The horizontal piece is fitted in the gap to hold the expanded state, and the vertical piece is a holding piece extending radially inward of the lock ring. According to a fourth aspect of the present invention, in the joining method according to the second aspect, the lock ring is divided into a plurality of pieces in the circumferential direction, and the divided divided pieces are connected by an elastic member so as to be expandable and contractible. In addition, the holding member is a holding ring that fits into the inner peripheral surface of the lock ring and holds the expanded state.

[0008]

As described above, when the diameter is increased, the inner diameter is larger than the outer diameter of the insertion opening projection, and when the diameter is reduced, the inner diameter is smaller than the outer diameter of the insertion opening so as to enclose the outer peripheral surface of the insertion opening. Therefore, it is no longer necessary to measure the gap between the split ends of the lock ring for confirming the mounting state of the lock ring, which has been essential in the past.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a vertical sectional front view showing a separation preventing pipe joint according to an embodiment of the present invention. Reference numeral 1 is one tube having a receiving opening 2, 3 is another tube having an inserting opening 4 to be inserted into the receiving opening, and an inserting projection 5 is provided on the outer peripheral surface of the distal end of the inserting opening 4 of the pipe 3. There is. An annular receiving recess 6 is formed on the inner peripheral surface of the receiving opening 2 substantially facing the insertion protruding portion 5, and the receiving opening is formed on the inner peripheral surface of the receiving opening 2 having a predetermined length from the receiving recess. An annular step portion 7 for locking the lock ring, which is shallower than the recess portion 6, is formed, and the inner peripheral surface of the receiving port 2 from the annular step portion to the receiving recess portion 6 faces from the receiving recess portion 6 to the annular step portion 7. The tapered portion 8 is formed so as to gradually reduce the diameter. As shown in FIG. 2, the ring-shaped stepped portion 7 is provided with a lock ring 10 which can be expanded / contracted in a circumferential direction.
Is fitted and locked to the outer peripheral surface of the. In the free state, the outer diameter of the lock ring 10 is such that it can pass through the receiving projection 11 adjacent to the annular step 7. That is, the diameter of the bottom surface of the receiving recess 6 is D ₀ , the outer diameter of the insertion protrusion 5 is D ₁ ,
Assuming that the inner diameter of the lock ring 10 is D ₂ , the outer diameter of the insertion port 3 is D ₃ , and the dimension between the annular step 7 and the outer diameter of the insertion port 4 (approximately equal to the thickness of the lock ring 10) is LH, the lock ring When 10 is expanded and temporarily placed between the insertion protrusion 5 and the receiving recess 6, D ₀ − (LH + LH)> D ₁ , in other words, D ₂ > D ₁
On the other hand, in the case of FIG. 1 in which the lock ring 10 is reduced in diameter and mounted on the annular step portion 7, there is a relationship of D ₁ > D ₂ .

Reference numeral 12 denotes a rubber ring interposed between the inner peripheral surface on the tip side of the receiving port 2 and the outer peripheral surface of the insertion port 4 facing the receiving port 2, and 13 denotes a push ring 14 for dividing the rubber ring 12 into two. Bolts and nuts that are pressed and fixed via 15 and the insertion port 4 between the tip of the rubber ring 12 and the socket projection 11.
Is a backup ring fitted and attached to the outer peripheral surface of the.

Next, the procedure for joining the two pipes 1 and 3 will be described with reference to FIGS. To join the socket 2 of one tube 1 and the socket 4 of the other tube 3, first, the lock ring 10
3A, (A), () in order to hold the state after passing through the receiving port projection 11 and temporarily placing it in the receiving port recess 6 and expanding the diameter of the temporarily placed receiving port recess 6 with a jig (not shown). The L-shaped holding piece 17 as shown in B) is set so that the lateral piece 18 thereof fits into the gap 19 between the surfaces of the split ends of the lock ring 10 which face each other (FIG. 3). When the holding piece 17 is set as described above, the vertical piece 16 extends radially inward of the lock ring 10.

Next, although not shown, the rubber ring 12 and the backup ring 15 are deposited on the outer peripheral surface of the insertion slot 4 and the insertion slot 4 is received.
(Fig. 4). Since the inner diameter D ₂ of the lock ring 10 at this time is larger than the outer diameter D ₁ of the insertion port projection 5, it can pass therethrough (FIG. 4). Then, the holding piece 17 is disengaged when the vertically oriented piece portion 16 is pushed rearward by the insertion opening projection portion 5 by passing through the insertion opening projection portion 5, whereby the lock ring 10 is again reduced in diameter and the insertion opening 4 is inserted. It fits so that it may cling to the outer peripheral surface (Fig. 5). The detached holding piece 17 is removed from the inside of the pipe. After a while
The insertion slot 4 is retracted toward the receiving end as shown in FIG.

Due to the retreat of the insertion opening 4, the insertion opening projection 5 is engaged with the lock ring 10, and the insertion opening 4 is further retracted in such an engaged state to lock the lock ring 10 with the taper portion 8. After that, it is positioned on the annular stepped portion 7 as shown in FIG. At this time, even if the entire circumference of the lock ring 10 is not in close contact with the outer peripheral surface of the insertion opening 4 (even if a part thereof is lifted up from the outer peripheral surface of the insertion opening 4), the lock ring 10 is pushed by the insertion opening projection 5 and received. It moves until it abuts the protrusion 11.

Next, the insertion opening 4 is pushed in to a predetermined position as shown in FIG. At this time, the lock ring 10 is locked to the annular step 7 by the locking means so that the lock ring 10 does not move together with the insertion slot 4.
An example of this locking means is shown in FIG. That is, (A) is a partial groove on the outer peripheral surface of the lock ring 10.
20 is formed, a locking member 21 made of a leaf spring is set in the groove, and a locking projection 22 of the locking member is formed in a position corresponding to the lock ring 10 in the annular step portion 23. It is inserted into and locked. (B) is a groove 24 formed on the lock ring 10.
Is formed deeper than the concave groove 23, and the locking member 25 set therein is composed of a coil spring 26 and a locking projection 27.
(C) shows an engaging portion 29 with a groove 28 formed in the lock ring 10 at the tip.
And a projection 32 having a flange 32 for engaging the locking member 31 with the engaging portion 29, the coil spring 34, and the opening 30. It is constituted by a screw 35 that can be screwed into the coil spring 34 to adjust the biasing force of the coil spring 34. As shown in FIG. 8, the lock ring 10 is locked to the annular step portion 7 and the insertion opening 4 is pushed to a predetermined position, so that the maximum bending allowance is obtained as compared with FIGS. In addition, the amount of escape and the amount of shrinkage can be allowed.

After the insertion of the insertion slot 4 is completed as described above, the backup ring 15 and the rubber ring 12 are pushed in to
Tighten the bolts and nuts 13 via 14 (Fig. 10). This work is the same as the conventional one. This completes the joining work.

FIG. 11 shows a modification of the lock ring. (A)
There are multiple lock rings 37 in the circumferential direction (2 in this example).
Each of the divided divided pieces 38 is divided into one piece, and the other divided end portions are flexibly connected by hinges 39 or the like so that the diameter can be reduced and expanded. (B) Lock ring 41
Is divided into a plurality of pieces (six pieces in this example) in the circumferential direction, and the divided ends of the divided pieces 42 are connected by a coil spring 43. The split ends of the split pieces 46 are replaced by the coil springs 43 and are connected by rubber rings 47. In this case, as shown in (D), the rubber ring 47 is a groove formed on the outer peripheral surface of each divided piece 46.
Fitted in 48. In the normal state, the lock rings 41 and 45 of (B) and (C) are reduced in diameter so that the divided ends of the divided pieces 42 and 46 are in contact with each other as shown by the chain line in the drawing, and are shown by solid lines due to the enlarged diameter. Like These lock rings 37, 41, 45 are also provided with locking means similar to those of the lock ring 10. For example, as shown in FIG. 12, a rubber ring 47 is provided as shown in a sectional view taken along line bb of FIG. Two are arranged. Note that FIG.
(A) corresponds to (A) of FIG. 9, (B) corresponds to (B) of FIG. 9,
9C corresponds to FIG. 9C.

FIG. 13 shows another embodiment of the present invention. 51 is a lock ring, and this lock ring 51 is shown in FIG.
It has the same structure as the lock rings 41 and 45 shown in (C). That is, the divided ends of each divided piece are connected by the elastic member 52 made of a spring, rubber or the like. Reference numeral 53 is a retaining ring that is used when the lock ring 51 is attached and has no split portion.
Left at 54. The outer diameter D ₄ of the holding ring 53 is slightly smaller than the inner diameter D ₅ of the receiving projection 11 and the inner diameter D ₆ of the receiving bottom 54 (D ₅ ≈D ₆ ). Since the configuration other than this is the same as that of the above-described embodiment, the same portions are denoted by the same reference numerals and the description thereof will be omitted.

Next, the joining procedure of this embodiment will be described with reference to FIGS.
This will be described with reference to 20. First, the lock ring 51 is passed through the socket projection 11 in a reduced diameter state and temporarily placed in the socket recess 6, and is similarly set on the outer peripheral surface of the holding ring 53 brought into the socket recess 6 (FIG. 14).

Next, although not shown, the rubber ring 12 and the backup ring 15 are deposited on the outer peripheral surface of the insertion slot 4 and the insertion slot 4 is received.
(Fig. 15). By this insertion, the holding ring 53 is pushed by the insertion port projection 5 and moved to the receiving port bottom portion 54 on the rear end side of the receiving port 2. Due to the movement of the insertion port 4 and the holding ring 53, the diameter of the lock ring 51 is reduced by the elastic member 52, and the lock ring 51 is fitted to the outer peripheral surface of the insertion port 4 so as to be held (FIG. 16). After that, 4
17 is retracted in the direction of the receiving end as in the case of the above embodiment. At this time, the retaining ring 53 remains on the receptacle bottom portion 54.

By the retreat of the insertion opening 4, the insertion opening projection 5 is engaged with the lock ring 51, and the insertion opening 4 is further retracted in such an engaged state to lock the lock ring 51 with the taper portion 8. After that, it is positioned on the annular stepped portion 7 as shown in FIG. Subsequent work is the same as that of the above-mentioned embodiment, and FIG.
FIG. 20 shows a state corresponding to FIG.

[0021]

According to the invention of claim 1, since the lock ring can be set only by inserting and moving the insertion opening, the lock ring before and after insertion into the receiving opening of the insertion opening can be provided. It is possible to eliminate the gap measurement at the split end of the lock ring, which is indispensable for checking the mounting state. Therefore, the workability is improved and the setting work of the lock ring can be performed very easily and reliably. In addition, since the work in the digging pit is reduced, the safety is improved. Claim 2
Since the invention of (1) is as described above, it is possible to easily hold the expanded state of the lock ring with the holding member, and to hold and release the lock ring with the insertion opening projection, so that the joining work can be efficiently performed. The inventions of claims 3 and 4 have an excellent effect that the holding by the holding member of the invention of claim 2 can be more specifically achieved by a holding piece or a holding ring.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a separation preventing pipe joint according to an embodiment of the present invention.

FIG. 2 is a front view of a lock ring used in the above.

FIG. 3A is a vertical sectional front view for explaining the operation, and FIG. 3B is a perspective view of a state in which the split end portion of the lock ring is held by a holding piece.

FIG. 4 is a vertical sectional front view for explaining the operation.

FIG. 5 is a vertical sectional front view for explaining the operation.

FIG. 6 is a vertical sectional front view for explaining the operation.

FIG. 7 is a vertical sectional front view for explaining the operation.

FIG. 8 is a vertical sectional front view for explaining the operation.

9A, 9B and 9C are partial sectional views of different locking means.

FIG. 10 is a vertical sectional front view for explaining the operation.

11A, 11B, and 11C are front views showing modifications of the lock ring, and FIG. 11D is an enlarged sectional view taken along line aa of FIG. 11C.

12 (A), (B), and (C) are different locks corresponding to (A), (B), and (C) of FIG. 9 along the line bb of FIG. 11 (C). It is a partial sectional view of a means.

FIG. 13 is a vertical sectional front view showing another embodiment of the present invention.

FIG. 14 is a vertical sectional front view for explaining the operation.

FIG. 15 is a vertical sectional front view for explaining the operation.

FIG. 16 is a vertical sectional front view for explaining the operation.

FIG. 17 is a vertical sectional front view for explaining the operation.

FIG. 18 is a vertical sectional front view for explaining the operation.

FIG. 19 is a vertical sectional front view for explaining the operation.

FIG. 20 is a vertical sectional front view for explaining the operation.

FIG. 21 is a vertical sectional front view showing an example of a conventional pipe joint.

22 is a cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

 1 One tube 2 Receptacle 3 Other tube 4 Insertion port 5 Insertion protrusion 6 Receptacle recess 7 Annular step 8 Tapered portion 10, 37, 41, 45, 51 Lock ring 11 Receptacle protrusion 12 Rubber ring 13 Bolt nut 14 Push ring 15 Backup ring 17 Retaining piece 21, 25, 31 Locking member 53 Retaining ring

Claims (4)

(57) [Claims] 1. An insertion opening of the other tube is inserted into the receiving opening of the one tube, and an insertion opening projection is provided on the outer peripheral surface of the tip of the inserted insertion opening.
The diameter can be expanded and contracted on the outer peripheral surface of the insertion opening on the tip side of the insertion opening from the insertion opening projection, and a lock ring that engages with the insertion opening projection and prevents the insertion opening from coming out of the reception opening is fitted. Fit together,
An annular seal member is interposed between the inner peripheral surface on the front end side of the receiving opening and the outer peripheral surface on the front end side of the insertion opening, and this seal member is pressed and fixed by a fastening member via a push ring to secure both pipes. In the pipe joint to be joined, when the diameter of the lock ring is expanded, the inner diameter is larger than the outer diameter of the insertion opening projection, and when the diameter is reduced, the inner diameter is smaller than the outer diameter of the insertion opening so as to enclose the outer peripheral surface of the insertion opening. It has a bottom inner diameter slightly larger than the outer diameter of the lock ring expanded on the inner peripheral surface of the receiving port facing the insertion port projection, and the lock ring can be temporarily placed when the lock ring is mounted. A mouth recess is formed, and an annular step portion for locking the lock ring is formed on the inner peripheral surface of the receiving opening that opposes the mounted lock ring, and the inner peripheral surface of the receiving opening between the annular step portion and the receiving recess is formed. A tapered portion is formed on the inner surface of the receiving recess so that the diameter gradually decreases toward the annular step. Disengagement prevention tube characterized in that locking means is provided on the inner peripheral surface of the step portion and the outer peripheral surface of the lock ring so as to lock each other when the lock ring is engaged with the annular step portion when the lock ring is mounted. Fittings. 2. The method for joining a separation preventing pipe joint according to claim 1, wherein the lock ring is temporarily placed in the receiving recess with the diameter reduced, and the lock ring is expanded in the temporarily placed receiving recess. In addition to the diameter, the expanded state is held by a holding member that is detachably attached to the lock ring so that the expanded state is released when pushed from the pipe axis direction by the insertion port projection, and then the annular sealing member is attached to the outer peripheral surface of the insertion port. Insert the insertion opening of the other tube that was deposited in the above into the receiving opening of the one tube, press the holding member with the insertion opening protrusion to remove it, and reduce the diameter by holding and releasing by this holding member A lock ring, which is held and fitted, is positioned and locked to the annular step portion by the insertion port protrusion that engages when the insertion opening is moved in the pulling direction from the receiving opening. After locking the A method for joining a separation preventing pipe joint, characterized in that the pipe joint is pushed into a predetermined position. 3. The lock ring is divided into one in the circumferential direction, and the holding member expands the diameter by inserting a lateral piece into the gap between the surfaces of the divided ends of the lock ring facing each other. The joining method for a separation preventing pipe joint according to claim 2, wherein the pipe piece is held and the vertically oriented piece portion is a holding piece that extends radially inward of the lock ring. 4. A lock ring is divided into a plurality of pieces in the circumferential direction, and each of the divided divided pieces is connected by an elastic member so as to be expandable and contractible, and a holding member of the lock ring. The method for joining a separation prevention pipe joint according to claim 2, further comprising a retaining ring which is fitted into the inner peripheral surface to retain the expanded state.